Reducing Measurement Time in Direct Interface Circuits for Resistive Sensor Readout.

Direct Interface Circuits (DICs) carry out resistive sensor readings using a resistance-to-time-to-digital conversion without the need for analog-to-digital converters. The main advantage of this approach is the simplicity involved in designing a DIC, which only requires some additional resistors an...

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Detalhes bibliográficos
Autores: Hidalgo-López, José A, Sánchez-Durán, José A, Oballe-Peinado, Óscar
Formato: artículo
Fecha de publicación:2020
País:España
Recursos:Instituto de Salud Carlos III (ISCIII)
Repositorio:Repisalud
Idioma:inglés
OAI Identifier:oai:repisalud.isciii.es:20.500.12105/18042
Acesso em linha:http://hdl.handle.net/20.500.12105/18042
Access Level:acceso abierto
Palavra-chave:Calibration methods
Direct interface circuits
Error analysis
Interface sensor
Resistive sensor
Time-based measurement
Descrição
Resumo:Direct Interface Circuits (DICs) carry out resistive sensor readings using a resistance-to-time-to-digital conversion without the need for analog-to-digital converters. The main advantage of this approach is the simplicity involved in designing a DIC, which only requires some additional resistors and a capacitor in order to perform the conversion. The main drawback is the time needed for this conversion, which is given by the sum of up to three capacitor charge times and their associated discharge times. This article presents a modification of the most widely used estimation method in a resistive DIC, which is known as the Two-Point Calibration Method (TPCM), in which a single additional programmable digital device pin in the DIC and one extra measurement in each discharge cycle, made without slowing down the cycle, allow charge times to be reduced more than 20-fold to values around 2 µs. The new method designed to achieve this reduction only penalizes relative errors with a small increase of between 0.2% and 0.3% for most values in the tested resistance range.